supposed to conduct the carbon monoxide safely outside, but hidden under a drop ceiling right under room 225, state investigators find the pipe is busted, full of holes, propped up with a vhs cassette tape and a hotel ice bucket, spewing poison gas into the room above. Mallatere, the manager, says he knew nothing of these problems. The attorney said soon after the jenn Kins were killed, the family warned the best western that they suspected carbon monoxide was to blame, before Jeffrey died. So they were warned before Jeffrey died that there would be a carbon monoxide problem? Absolutely. By the family of the people who had just been killed in that room and they didn't do anything about it? Apparently if they did, it wasn't enough. The hotel manager at the time says authorities never mentioned carbon monoxide and just this week "20/20" obtained a report by North Carolina state licensing authority that reveals that over the course of a decade, contractors and town inspectors missed multiple clues that may have prevented the deaths of all three victims. Do you feel any responsibility for what happened? I don't believe that anybody in any way involved, whether it be the authorities or the contractors or my employees, or myself should go to bed tonight and not feel responsibility. What you're saying is it doesn't mean you're criminally culpable? I would never willfully hurt a guest if I knew that I could keep that from happening. The most outrageous failure of all? The state tells "20/20" it sent Shirley Jenkins toxicology report showing she had been killed by carbon monoxide to medical examiner Brent hall on June 3rd, in plenty of time to save a little boy's life. Jeffrey Williams would not check in for another four days, but not a peep from Dr. Brent hall, not single warning. Is it possible that had the medical examiner who had the report, the autopsy, saying that it was carbon monoxide poisoning, that it killed the Jenkins in the same room in which Jeffrey Williams was saying and he had delivered that report to the police, that Jeffrey would still be alive? I absolutely agree with that. We went to Dr. Hall's office where the receptionist was unreceptive. I'm Matt Gutman from ABC news. I'm not interested. Hall resigned as the medical examiner. In January the grand jury handed out three counts of involuntary manslaughter and aggravated assault for the Williams injuries. The da's office decided to submit to the grand jury one name, and that name being Barry Damon mallatere. How often do you think about this? Every day. That boy, that elderly couple. Every day. I need to cut. Unlike smoke detectors, there is no federal requirement for carbon monoxide detectors in hotel rooms. Some states, now including north Carolina, do require them. Pennsylvania does not. That's where another best western hotel pool heater malfunctioned over the weekend, causing carbon monoxide into the rooms. 200 people were evacuated, 28 of them sent to area hospitals. So turning grief into good works, the Williams family created jeffreysfoundation.org to raise awareness about carbon monoxide poisoning. It's very simple. Carbon monoxide detectors are cheap in the grand scheme of life. Next, extreme vacations or

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